A homolog of human C-reactive protein (CRP) and amyloid P-component (AP) is present in the Syrian hamster as a sex limited protein called female protein (FP). FP functionally is similar to both CRP and AP as it has a Ca plus plus dependent phosphorylcholine binding site and is a component of hamster amyloid. FP also is involved in the inflammatory response, however, changes in serum concentration are sex limited. Catabolism of FP is similar in both sexes, although differences in distribution suggest specific transport or receptor mechanisms.